Heat sink for an electronic device of a motor vehicle and method of manufacturing same

Abstract

An inverter assembly for a motor vehicle includes a housing with an inlet end for receiving a flow of coolant and an outlet end for discharging the flow of coolant. The assembly further includes a first plurality of power transistors conducting and switching an electrical current and generating a first amount of heat. The assembly further includes a second plurality of power transistors conducting and switching the electrical current and generating a second amount of heat that is less than the first amount of heat. A heat sink includes a plate with a first section adjacent to the first plurality of power transistors and a second section adjacent to the second plurality of power transistors. The heat sink further includes a first plurality of fins for drawing the first amount of heat from the first section and a guide vane directing the flow of coolant toward the first plurality of fins.

What is claimed is: 
     
       1. An inverter assembly for a motor vehicle, the inverter assembly comprising:
 a housing having an inlet end for receiving a flow of coolant and an outlet end for discharging the flow of coolant from the housing, wherein the inlet end is disposed on the housing opposite the outlet end along a longitudinal axis of the housing; 
 a first plurality of power transistors mounted to the housing between the inlet end and the outlet end, with the first plurality of power transistors conducting and switching an electrical current and generating a first amount of heat; 
 a second plurality of power transistors mounted to the housing between the inlet end and the outlet end, with the second plurality of power transistors conducting and switching the electrical current and generating a second amount of heat that is less than the first amount of heat; and 
 a heat sink mounted to the housing between the inlet end and the outlet end, with the heat sink comprising:
 a plate having a first section positioned adjacent to the first plurality of power transistors to draw the first amount of heat from the first plurality of power transistors and a second section positioned adjacent to the second plurality of power transistors to draw the second amount of heat from the second plurality of power transistors; 
 a first plurality of fins extending from the first section of the plate to draw the first amount of heat from the first section; 
 a second plurality of fins extending from the second section of the plate to draw the second amount of heat from the second section; and 
 a guide vane extending directly from the plate between the first section and the second section, the guide vane oriented obliquely relative to the longitudinal axis, 
 
 wherein the guide vane directs a first portion of the flow of coolant from the inlet end towards the first section to cool the first plurality of fins, and directs a second portion of the flow of coolant from the inlet end towards the second section to cool the second plurality of fins before the coolant exits the housing at the outlet end, wherein the first portion is larger than the second portion such that the first section receives more coolant than the second section. 
 
     
     
       2. The inverter assembly of  claim 1 , wherein the first plurality of fins are positioned on a first side of the longitudinal axis and the second plurality of fins are positioned on a second side of the longitudinal axis, and one end of the guide vane closest the inlet end is positioned on the second side of the longitudinal axis and an opposite end of the guide vane closest the outlet end is positioned on the first side of the longitudinal axis. 
     
     
       3. The inverter assembly of  claim 2 , wherein the guide vane is a non-linear flange extending from the plate. 
     
     
       4. The inverter assembly of  claim 3 , wherein the non-linear flange extending from the plate has an arcuate shape. 
     
     
       5. The inverter assembly of  claim 2 , wherein the guide vane is a linear flange extending from the plate and positioned at an angle relative to the longitudinal axis. 
     
     
       6. The inverter assembly of  claim 2 , wherein the plate further comprises a third section positioned downstream of the inlet end and upstream of the first and second sections of the plate, with the third section being free of the first plurality of fins and the second plurality of fins, and the end of the guide vane closest the inlet end is disposed at least partially within the third section. 
     
     
       7. The inverter assembly of  claim 6 , further comprising a third plurality of power transistors mounted to the housing and positioned adjacent to the third section of the plate, with third plurality of power transistors conducting and switching the electrical current and generating a third amount of heat that is less than the first amount of heat. 
     
     
       8. An inverter assembly for a motor vehicle, the inverter assembly comprising:
 a housing having an inlet end for receiving a flow of coolant and an outlet end for discharging the flow of coolant from the housing, wherein the inlet end is disposed on the housing opposite the outlet end along a longitudinal axis of the housing; 
 a first plurality of power transistors mounted to the housing between the inlet end and the outlet end, with the first plurality of power transistors conducting and switching an electrical current and generating a first amount of heat; 
 a second plurality of power transistors mounted to the housing between the inlet end and the outlet end, with the second plurality of power transistors conducting and switching the electrical current and generating a second amount of heat that is less than the first amount of heat; and 
 a heat sink mounted to the housing between the inlet end and the outlet end, with the heat sink comprising:
 a plate having a first section positioned adjacent to the first plurality of power transistors to draw the first amount of heat from the first plurality of power transistors and a second section positioned adjacent to the second plurality of power transistors to draw the second amount of heat from the second plurality of power transistors; 
 a first plurality of fins extending from the first section of the plate to draw the first amount of heat from the first section, with each of the first plurality of fins having a frustum pin shape; 
 a second plurality of fins extending from the second section of the plate to draw the second amount of heat from the second section, with each of the second plurality of fins having the frustum pin shape; and 
 a guide vane extending directly from the plate between the first section and the second section, the guide vane oriented obliquely relative to the longitudinal axis, wherein the guide vane directs a first portion of the flow of coolant from the inlet end towards the first section to cool the first plurality of fins, and directs a second portion of the flow of coolant from the inlet end towards the second section to cool the second plurality of fins before the coolant exits the housing at the outlet end, wherein the first portion is larger than the second portion such that the first section receives more coolant than the second section. 
 
 
     
     
       9. The inverter assembly of  claim 8 , wherein the frustum pin shape extends along a pin axis, and the frustum pin shape has a surface positioned at a draft angle in a range between 7 degrees and 9 degrees relative to the pin axis. 
     
     
       10. The inverter assembly of  claim 9 , wherein the first plurality of fins and the second plurality of fins are arranged in a staggered pattern relative to one another. 
     
     
       11. The inverter assembly of  claim 10 , wherein the first plurality of fins are positioned on a first side of the longitudinal axis and the second plurality of fins are positioned on a second side of the longitudinal axis, and one end of the guide vane closest the inlet end is positioned on the second side of the longitudinal axis and an opposite end of the guide vane closest the outlet end is positioned on the first side of the longitudinal axis. 
     
     
       12. The inverter assembly of  claim 11 , wherein the guide vane is a non-linear flange extending from the plate. 
     
     
       13. The inverter assembly of  claim 12 , wherein the non-linear flange extending from the plate has an arcuate shape. 
     
     
       14. The inverter assembly of  claim 13 , wherein the plate further comprises a third section positioned downstream of the inlet end and upstream of the first and second sections of the plate, with the third section being free of the first plurality of fins and the second plurality of fins, and the end of the guide vane closest the inlet end is disposed at least partially within the third section. 
     
     
       15. The inverter assembly of  claim 14 , further comprising a third plurality of power transistors mounted to the housing and positioned adjacent to the third section of the plate, with third plurality of power transistors conducting and switching the electrical current and generating a third amount of heat that is less than the first amount of heat. 
     
     
       16. A method, executed by a computer having a non-transitory computer readable storage medium storing instructions and at least one processor, of manufacturing an inverter assembly for a motor vehicle, the method comprising:
 simulating, using the at least one processor, a virtual inverter assembly to determine a thermal performance of the virtual inverter assembly, with the virtual inverter assembly including:
 a housing having an inlet end for receiving a flow of coolant and an outlet end for discharging the flow of coolant from the housing, wherein the inlet end is disposed on the housing opposite the outlet end along a longitudinal axis of the housing; 
 a first plurality of power transistors mounted to the housing between the inlet end and the outlet end, with the first plurality of power transistors conducting and switching an electrical current and generating a first amount of heat; 
 a second plurality of power transistors mounted to the housing between the inlet end and the outlet end, with the second plurality of power transistors conducting and switching the electrical current and generating a second amount of heat that is less than the first amount of heat; and 
 a heat sink mounted to the housing between the inlet end and the outlet end, with the heat sink comprising:
 a plate having a first section positioned adjacent to the first plurality of power transistors to draw the first amount of heat from the first plurality of power transistors and a second section positioned adjacent to the second plurality of power transistors to draw the second amount of heat from the second plurality of power transistors; 
 a first plurality of fins extending from the first section of the plate to draw the first amount of heat from the first section; 
 a second plurality of fins extending from the second section of the plate to draw the second amount of heat from the second section; and 
 a guide vane extending directly from the plate between the first section and the second section, the guide vane oriented obliquely relative to the longitudinal axis, 
 
 wherein the guide vane directs a first portion of the flow of coolant from the inlet end towards the first section to cool the first plurality of fins, and directs a second portion of the flow of coolant from the inlet end towards the second section to cool the second plurality of fins before the coolant exits the housing at the outlet end, wherein the first portion is larger than the second portion such that the first section receives more coolant than the second section; 
 
 determining, using the at least one processor, a temperature gradient between the first plurality of fins and the second plurality of fins; 
 comparing, using the at least one processor, the temperature gradient to a gradient threshold; 
 positioning, using the at least one processor, the guide vane at a new position based on the temperature gradient to form a new virtual inverter assembly, in response to the computer determining that the temperature gradient is above the gradient threshold; 
 simulating, using the at least one processor, the new virtual inverter assembly to determine the thermal performance of the new virtual inverter assembly, in response to the computer forming the new virtual inverter assembly; and 
 forming the inverter assembly based on the new virtual inverter assembly in response to the computer determining that the temperature gradient is below the gradient threshold. 
 
     
     
       17. The method of  claim 16 , further comprising positioning, using the at least one processor, the guide vane at predetermined angular position relative to the longitudinal axis in response to the computer determining that the temperature gradient is above the gradient threshold. 
     
     
       18. The method of  claim 17 , further comprising:
 comparing, using the at least one processor, a fin temperature of each of the fins, to a predetermined temperature threshold; 
 omitting, using the at least one processor, a third plurality of fins from a third section of the plate to form a new virtual inverter assembly, in response to the computer determining that the fin temperature of the associated fins is below the predetermined temperature threshold; 
 simulating, using the at least one processor, the new virtual inverter assembly to determine the thermal performance of the new virtual inverter assembly, in response to the computer forming the new virtual inverter assembly; and 
 forming the inverter assembly based on the new virtual inverter assembly in response to the computer determining that the fin temperature of each of the first plurality of fins and the second plurality of fins is above the predetermined temperature threshold.